October 2009 Archive for In the Shop

As a farm machinery mechanic and writer, Dan brings a hands-on approach that only a pro can muster. Along with his In the Shop blog, Dan writes a column by the same name as well as the Shop Series for Farm Journal magazine. Always providing practical information, he is a master at tackling technical topics and making them easy for all of our readers to understand. He and his wife, Becky, live near Bouton, Iowa.

Many farm equipment dealerships no longer have diagnostic and repair manuals for machinery manufactured since 2000. Instead of buying a half dozen or more printed-on-paper manuals that cost $200 to $700 per copy, most dealership now opt for manuals on CDs or DVDs that mechanics use with laptop computers. The software is copyrighted and sold ONLY to dealerships that meet strict guidelines established by the parent company.

The benefits and problems of having everything on laptops is a good topic for a future blog, but for now, heed this warning: At least one, maybe more, internet buy/sell websites have sellers offering software programs identical to what mainline farm equipment manufacturers sell to dealerships. The software is advertised to have everything that dealership software has, including diagnostic and repair procedures for all the tractors, combines, harvesters, planters, sprayers and tillage equipment offered by that manufacturer. The implication is that if a farmer buys this software he will have access to all the tech manuals available to dealerships.

Maybe so. But what isn't told is that most equipment manufacturers issue regular updates to their tech support software programs. And written into those programs are "time bombs" that, after 60 days, 4 months, maybe one year, the software programs do a Mission Impossible and self-destruct so they are no longer readable by a computer.

If the idea of buying "genuine" dealership tech manuals over the internet is tempting, be aware that those manuals may work great for a week, a month, maybe a year. Then built-in protection sub-programs will erase or make unreadable the information within the program.

If a farmer desperately wants to have a dealership tech manual for a particular tractor, combine or other piece of equipment so they can do more diagnosis and repairs themselves, printed-on-paper manuals are still available through dealerships for most farm equipment. Some dealers are reluctant to sell paper tech manuals to customers; others figure anybody willing to pay the price has the right to the information about that single piece of farm equipment. Whether to invest several hundred dollars in a specific tech manual for a high-maintenance piece of equipment like a combine, cotton harvester, baler or sprayer depends on how much work on the machine the farmer intends to do himself over the lifetime of the machine.

But it's a sure thing that spending the money on pirated computer software is probably not a long-term investment because all the buyer will eventually end up with is blank, unreadable computer disks. If it's any consolation...what I've heard from second-hand sources who have been reliable in the past is that the mainline equipment manufacturers are going to land on software pirates with all the power their corporate lawyers can muster. Very soon and very hard.

Maybe you agree with the mainline equipment manufacturers. Maybe you're sympathetic to the software pirates. My concern is that farmers will spend hundreds of dollars and end up with nothing.

Before I dive into a rant about how engineers design farm machinery without consideration for making repairs, I must acknowledge that in many cases engineers actually do an excellent job designing components to make repairs easier.

BUT. There are times when you're lying upside down, twisted at a 45-degree angle with both arms extended over your head at different angles, that you sincerely wish the engineer who designed the machine could be there with you to share the experience. Or at least show you how to get the #&$! thing apart.

Aside from comfort, safety and sheer convenience, it's also annoying when designers choose to use fasteners or components that require special tools. There's nothing worse than being deep into a complicated repair project only to discover a critical bolt or fastener is a special design that requires an odd-ball tool that even the local Snap-on tool dealer has never heard of. (But he'll gladly order you one for $150.)

Electrical harness connectors are especially bad for that. I have a small box crammed at last count with more than 25 different "pin-pushers" to remove individual sockets or pins from electrical connectors.Yet I still cringe every time I have to take apart and repair a big electrical connector because there's a good chance I won't have the correct tool.

I'm not the only one intimidated by the myriad types and sizes of pins/sockets used in modern farm equipment electrical systems. One of our parts men, with more than 20 years experience and an encylopedic memory, has been known to hide underneath the counter if he sees a mechanic come toward the parts counter carrying a frazzled wiring harness connector.

I'm sure engineers do the best they can to make equipment not only durable, but repairable. But there are days when I imagine a group of engineers sitting around a computer, saying to each other, "Wait till they try to take THIS one apart....!"

I did it again. I allowed computer technology to overshadow common sense.

A light on a combine didn't work. Common sense says the first step is to replace the bulb, or at least test for voltage at the socket. When I stepped out of my truck the customer assured me that he had already "replaced the bulb with one I robbed from another light on the combine," so I hopped in the combine cab and used the on-board diagnostic system to see what was the problem. After several hours of testing voltages and resistances at a dozen or more electrical connectors in a half dozen wiring harnesses, and experimenting with replacing a $900 computer board that did nothing to make the faulty light work properly, I calmed down and used common sense. I replaced the bulb, and the light worked. Duh. The customer is still scratching his head trying to figure out why switching lights didn't identify that the bulb was bad. But the bottom line is that the first step in diagnosing any problem is to do the easy, obvious stuff before the sexy, high-tech, complicated stuff.

For those of you who like technical stuff, here's a warning based on my little escapade: Remember when lights were turned off and on by a simple switch that did or didn't allow current to flow through the lights' positive wire? Not any more. That one light--which happened to be on the unloading auger--is powered and controlled through a computer board that takes the on/off signal from the main light switch, compares it to sensors that track whether the unloading auger is swung in or out, adds inputs from the overall lighting system controller, then decides whether to turn the light on or off by opening or closing the NEGATIVE side of the light's circuit.

Maybe my view is biased because I spent so many hours unplugging combines this past week, but soybean stalks seem unusually tough and rubbery this year. Some farmers say it's due to improved genetics that create sturdier stalks. Others think it's due to spraying with fungicides that keep stalks alive and green longer. Delayed frost has certainly allowed full-season varieties to stay "green" and challenge the capacity of combines.

A secondary result is the stubble of harvested beans seems unusually stiff and coarse this fall. I've ran into a couple situations where performance of automatic header height control systems was diminished by stiff stems. On 30- and 35-foot-wide platforms the stubble was actually stiff enough to hold the skid shoes up so the auto height system thought it had encountered a rock, causing it to lift the platform and create a "hopping" pattern through the field. Tipping the cutterbar slightly down made it more aggressive and allowed the platform to cut smoothly.

If soybean stems are stiff enough to "float" combine platforms, it's going to be interesting to see what sort of tire damage we get when guys start fall-applying nitrogen.

There's not much we can do about green-stemmed soybeans plugging combines except hope for a frost and drier weather. Unless it would be to use a softer touch on the hydro-handle whenever the combine approaches an area of green-stemmed beans. IN MY EXPERIENCE--if you wait until the "low engine rpm" warning light comes on before you pull back on the hydro-handle, you've waited too long. Plan on spending a couple delightful hours digging those green-stemmed beans out of some portion of your combine's innards.

On the positive side, I've learned some valuable tricks about unplugging combines. You can sometimes cut tangled, packed stems with a reciprocating saw (like a Sawzall). Depending on which component is plugged, a cable-winch attached to an axle or immobile object can rotate a plugged component and loosen the plug. In extreme cases it's necessary to cut the bolts holding the concave to relieve enough pressure to dig out the machine.